Impeller type pump having seal means and protective means

摘要

An impeller type pump has a pump body defining a pump chamber therein, and an impeller disposed in the pump chamber having a center shaft. A hollow cylindrical connector is mounted in the center shaft having internal screw threads engageable with external screw threads on the end of a drive shaft for rotating the impeller. The connector is provided with thermal expansion-absorbing slits arranged in equally spaced relation along the circumference of the connector which extend lengthwise of the connector with an unslit portion left on that end of the connector which is close to the other end of the drive shaft.